A public address system for the sonication of a sonication region is proposed. The public address system has a multiplicity of loudspeakers arranged in the sonication region for outputting an input signal as an output signal. The public address system also comprises a measuring device for detecting the audio signal at a measurement point in the sonication region, wherein the measuring device is designed to determine a propagation time difference of the audio signals between each of two loudspeakers to the measurement point and to provide the propagation time difference and as propagation time difference data. The public address system also comprises a delay module, wherein the delay module is designed to add a time delay to the input signals based on the propagation time differences, in order to compensate for the propagation time difference between the audio signals at the measurement point. A method for the sonication of the sonication region and a computer program for the implementation of the method are also proposed.
In professional public address systems a plurality of separate loudspeakers is often used, in particular for different frequency bands. For the sonication of larger areas, in addition to a central loudspeaker system on the stage, further distributed speaker systems are used to achieve a uniform sound distribution throughout the audience area. Because of the different positions of the individual speakers, the distances and therefore the sound propagation times to the sonication region are also different. In order to avoid the audio signals arriving at the listener at different times and generating unwanted effects, the output signals for the loudspeakers closer to the audience area must be delayed. For this purpose, the audio signals are detected by a specialist and the measurement values determined are implemented in the audio system manually.
Document EP 2 286 601 B1, which probably represents the closest prior art, relates to a conference audio system. The conference audio system has a plurality of delegate units, wherein each delegate unit has a delegate loudspeaker and a delegate microphone. The conference audio system also comprises a control element for distributing at least one audio signal from at least one delegate microphone or from another sound source to a plurality of delegate loudspeakers, wherein the plurality of delegate loudspeakers generates a common audio atmosphere. A delay element is designed to add a time delay to the audio signal, wherein the time delay depends on the distance between the position of the delegate microphone or the sound source which generates the audio signal and the individual delegate loudspeaker position. The time delay is added so as to add a direction characteristic or direction property to the common audio atmosphere, which has been generated with the involvement of the generated audio signal.